Lantus versus Levemir

February 2nd, 2011

insulin syringe

Choosing a long-acting insulin can be daunting, especially since both Lantus (insulin glargine) and Levemir (insulin detemir) are similar in many respects. There are a few key differences that will help you and your doctor make the decision about which insulin to use.

Both Lantus and Levemir are injected subcutaneously, either with a syringe or insulin pen, and both can be used with fast-acting insulin at meal times to aid with diabetes control. Neither forms of long-acting insulin should be diluted, or mixed with other insulin products. Lantus and Levemir have a 1:1 ratio, but will be accepted by the body differently from patient to patient; any changes to diabetes medication and dosage should always be discussed with a doctor.


Lantus (insulin glargine) is marketed as a "peakless" insulin option, with an 18-26 hour action period. It is injected once a day, at the same time every day to maintain regularity. One of the biggest advantages of Lantus is that, due to its lack of peak, it decreases the risk of nocturnal hypoglycemia.

Some doctors suggest that Lantus be taken twice daily, even though it is approved to be taken once daily. Lantus may not be the best option for people with irregular schedules, as its long action time gives less control (it can take up to three days to complete its action). As with other long-acting insulin, Lantus can be used with fast-acting insulin at meal times.


Levemir (insulin detemir) is a long-acting insulin with a 9-12 hour action period. It is injected twice a day, morning and night. Because one of its peak periods can occur at night, when glucose levels are often lower, it poses an increased risk of nocturnal hypoglycemia, and should not be used by patients with hypoglycemia.

Levemir has the advantage or greater diabetes control, because it is taken more frequently. And while patients using Levemir often use a higher insulin dosage, they often experience less weight gain than patients using Lantus.

Choosing a long-acting insulin comes down to what works best for the individual in question, taking into account the body's interaction with the insulin, as well as factors such as lifestyle and eating habits.Any decision involving diabetes medication should be made with the help of a doctor or other health-care provider.